Engine Management TechnologyDUAL INJECTORSThe Kawasaki KX250F was the first mass-production motocross bike to feature Dual Injectors. One injector is located downstream of the throttle valve, where injectors are located on standard FI systems, and a second is located upstream of the throttle valve, close to the airbox. The two injectors split their roles: operating at different rpm ranges, they ensure both smooth, instant response at low-rpm and high peak power at high-rpm. For cases that call for low-rpm operation like instantaneous acceleration off the start and precise control when cornering, primary operation falls to the downstream injector. Because it is positioned close to the combustion chamber, sprayed fuel can be supplied to the engine quickly, resulting in sharp response. Conversely, when high power is the priority, primary operation switches to the upstream injector, which focuses on high-rpm applications. Its location farther away from the combustion chamber means that the fuel has a longer travel time. This allows more time for the fuel particles and air to mix, as well as allowing the mixture to cool and condense. This means that when more power is needed, the cylinder can be filled with a greater quantity of high-quality mixture.
|
Chassis Management TechnologyERGO-FITProper fit is key for rider comfort and control. However, the ideal fit varies from rider to rider, depending on their physical dimensions and riding style.
ERGO-FIT is an interface system designed to allow riders to find their ideal riding position. Various points of the chassis interface (the handlebar, footpegs and seat, etc.) can be adjusted through a combination of interchangeable parts and parts with adjustable positions. This enables a wide range of riders to find a riding position that offers both comfort and control. Feeling at one with their machine, they will be able to experience how Kawasaki machines are fun and rewarding to ride. *Adjustable parts and their range of adjustability vary by model. positions. This enables a wide range of riders to find a riding position that offers both comfort and control. Feeling at one with their machine, they will be able to experience how Kawasaki machines are fun and rewarding to ride. *Adjustable parts and their range of adjustability vary by model. |
FACTORY-STYLE ENGINE COMPONENTS AND TUNINGChampionship-proven PerformanceRecognized as the most powerful motocrosser in the paddock, the KX450 boasts innovative engine technology inspired by Kawasaki’s race machines. Features like finger-follower valve actuation and a bridged-box bottom piston that contribute to its lofty performance are backed by electric start and a hydraulic clutch, further elevating its race-winning potential. |
SERIOUSLY POWERFUL ENGINEThe high-acclaimed KX450 engine delivers hard-hitting power, while its flat torque curve makes it easy to get on the gas. Finger-follower valve actuation (a valve train designed by Kawasaki’s World Superbike engineers) enables large-diameter valves and aggressive cams. Downdraft-style intake and friction-reduction efforts (like a dry film lubricant on the piston skirt) further contribute to the high performance. |
ELECTRIC STARTBeing able to restart an engine quickly during a race can mean the difference between keeping your lead, or having to fight your way back through the pack. Electric start makes restarting the engine as easy as pushing a button. |
HYDRAULIC CLUTCHThe hydraulic clutch offers direct feel and light lever action. Revised construction using coned-disc springs results in lighter clutch actuation when the lever has been pulled in, and a wider clutch engagement range, which facilitates control (especially when half-clutching). |
ADJUSTABLE MX ECULightweight and designed for the rigours of off-road riding, the ECU contains multiple programmable engine maps to offer riders an advantage on the race course. Using the provided DFI couplers, riders are able to easily switch from one to another of the three engine maps to suit riding conditions. The plug-and-play style system is quick, easy and stress-free. Each of the three maps can be reprogrammed using the optional KX FI Calibration Kit. |
LAUNCH CONTROLFactory-style launch control system increases the chance of getting a good start by helping riders maximise grip when starting on a low-traction surface. |
FACTORY-STYLE CHASSIS COMPONENTS AND TUNINGLight, Nimble HandlingTrimmed of all unnecessary material, this is the leanest KX450 chassis to date. Frame, suspension, brakes and ergonomics have all been optimized to make the KX450 even better equipped to turn quick lap times. |
FRAME
Complementing the powerful engine, light, nimble handling contributes to the KX450’s quick lap times. Thanks to extensive weight-reduction efforts, the lightweight aluminum perimeter frame contributes to a highly-competitive, low overall weight of only 110.2 kg. |
SUSPENSIONRace-Ready SuspensionHandling suspension duties up front is a high-performance ø49 mm inverted coil-spring fork. The large-diameter inner tubes (the same size as on our factory racers) enable the use of large damping pistons, delivering smooth action and firm damping. At the rear, New Uni Trak rear suspension contributes to superb rear-wheel traction. |
BRAKESStrong Stopping PowerThe oversized ø270 mm semi-floating front disc complemented by a ø250 mm disc at the rear deliver strong stopping power and a high level of control.The oversized ø270 mm semi-floating front disc complemented by a ø250 mm disc at the rear deliver strong stopping power and a high level of control. |
BODYWORKSlim, Ergonomic BodyworkThe narrow frame and minimalistic bodywork offer a slim riding position that facilitates control.
|
ADJUSTABLE ERGONOMICSGet the Perfect FitA choice of four handlebar positions and two footpeg positions allows riders to tailor their riding position to suit body size and preference. Factory-style ø28.6 mm (1-1/8”) Renthal aluminum Fatbar helps reduce vibration and shocks transmitted to the rider, while a lower, closer grip position helps put the rider in a position that makes it easier to weight the front wheel. |
FEATURING
ADDITIONAL VEHICLE FEATURES